Like I said in my farewell to CSS post, I don't use CSS directly anymore. And things have been this way for years now. I also have been tired of PostCSS (because I disagree with the vision and the directions taken by the project).

Beside the fact that I were not using CSS directly anymore, too many PostCSS releases meant that I had to update most of the PostCSS plugins underneath cssnext in order to adapt to the new or changed APIs. This was a very time consuming process. At the time being one of the most active PostCSS contributors, I wasn’t always warned about these API changes. This eventually motivated me to just stop contributing to this ecosystem, even if I created the PostCSS GitHub organization in the first place.

Why didn't you give the project to someone else?

I tried. I gave 3 of the most active contributors in the cssnext/PostCSS ecosystem rights over the repo, but given everyone’s time and priorities, it wasn’t enough to ensure the project would be sufficiently maintained.

I also tried to ask for help via Twitter, but no response.

Then one active member of PostCSS organization made a fork (kind of) and it's probably better already than cssnext ever was. If you still want to use CSS, you should take a look at it.

Why don't you just let this thing rot?

That's not my type. I tried to maintain the package for a while, as the number of downloads prove that people are actually using it. But now that a solid alternative is around (postcss-preset-env), I think it's time to deprecate cssnext.

Migration to postcss-preset-env

Migration should be pretty easy.

In short, just replace postcss-cssnext with postcss-preset-env and choose your stage.